Here's a reply I posted to a similar question. Sorry for the "used" comment, but saves a lot of typing:
So sorry this has become chronic for you. It happens to me maybe once every two or three months. I think I have it narrowed down to eggs. Anyway...the pain is simply indescribable, but I'll try: it's like a breathing-paralyzing, wide-eyed, out-of-body experience, spinning-through-the-Milky-Way-seeing-stars type of pain. The bidet helps all of the normal stuff except this.
I recently found the one thing that has cut the pain to the point where I can breathe again: 5% lidocaine cream in the hemorrhoid department at Walgreen's. Walgreen's brand. Around $20 for the tube. I'm sure any 5% lidocaine cream will help, but I've never found 5% anywhere else. 4% is prevalent, but not 5%. I haven't inquired, but I suppose my GI doc could prescribe something even stronger if it's available. Anyway...after bideting and drying, yes, it does need to be applied "inside". But, it works.